JP4161981B2 - Communication device and program - Google Patents

Description

  The present invention relates to a communication device that acquires data necessary for setting an address from a device in a network and automatically sets the address to the device itself, and a program used therefor.

  Conventionally, as a communication apparatus, an IP (Internet Protocol) address issuance (lease) is requested from a DHCP (Dynamic Host Configuration Protocol) server in the network, and is issued (lease) from the DHCP server by communication at this time. It is known to set a set IP address in its own device so that it can participate in a TCP / IP network.

  In addition, a part of the IP address (for example, a network address) to be set to the own device is acquired from a router having a role of connecting the network to another network, and an address unique to the own device is generated, and the above acquisition is performed. It is also known that an IP address generated by combining a part of the IP address is set in the own device so that the own device can participate in the TCP / IP network.

In addition, the communication device has a restriction table that describes IP addresses that permit access and IP addresses that prohibit access, and has a function of restricting access from external devices based on this restriction table. Communication devices are known. This communication apparatus is convenient because unauthorized access from outside can be prohibited.
JP 2002-333958 A

  However, in the communication apparatus described above, even when an incorrect IP address is registered in the restriction table, access is restricted according to the restriction table. Therefore, access from a DHCP server that should not restrict access should be restricted. There was a case that would limit.

  If access to the communication device from the DHCP server becomes impossible due to an incorrect setting operation on the restriction table, the communication device cannot set / update its own IP address, and as a result In addition, it becomes impossible to participate in the TCP / IP network.

  Of course, such a problem does not occur unless the administrator registers an incorrect IP address in the restriction table. However, in a device that allows the administrator to specify a range of permitted or prohibited IP addresses, the range of prohibited IP addresses. Even though the IP address of a device that needs to be accessed in order to set the IP address of its own device, such as a DHCP server or a router, is contained in the administrator, the administrator may not be aware of it. Also, when registering an IP address that permits access, attention is paid to the IP address registration operation for devices other than the DHCP server, and the administrator forgets the registration operation for the IP address of the DHCP server or the like. There was a case.

  The present invention has been made in view of these problems, and an object of the present invention is to prevent an address from being automatically set by a communication device due to a setting error of an administrator by the communication device.

The communication device according to claim 1, which has been made to achieve the above object, communicates with a network interface and a device in the network via the network interface, and executes processing based on data received via the network interface. The receiving means accepts the received data by the execution means, the acceptance judging means for judging whether or not the data received by the network interface is accepted based on the address on the network assigned to the transmission source device of the received data. If it is determined that the received data is discarded, the first execution control causes the processing execution unit to execute processing based on the received data if the reception determining unit determines to receive the received data. Received data is accepted by the means and acceptance judging means Data determination for determining whether or not the received data is data necessary to set an address on the network transmitted from a specific type of device in the network to the communication device. If the received data determined not to be accepted by the means and the acceptance judging means is data necessary for setting the address on the network to the communication device by the data judging means, the first execution And a second execution control unit that prohibits discarding of the received data by the control unit and causes the process execution unit to execute a process of setting an address in the communication device based on the received data .

In the present invention, when the received data is data necessary for setting the address as described above, the discarding of the received data is prohibited, and the process executing unit performs the process of setting the address in the communication device. I made it.

Therefore, according to the present invention, even when the user makes a setting for prohibiting access from a specific type of device in the network such as a DHCP server , the first execution control means To avoid interference. Therefore, according to the present invention, it is possible to prevent an address from being automatically set by the communication device due to a setting error of the administrator by the communication device.

  In order to prevent the automatic setting of an address due to an administrator's mistake, it is possible to configure the communication device so that the conventional filtering function is not turned on until the address is set in the own device. . However, an expiration date is generally set for an IP address issued by a DHCP server or the like. Therefore, even if the communication device is configured so that the filtering function is not turned on until the address is set in the own device, if the expiration date is set in the issued IP address, there is an error of the administrator. Then, the second and subsequent address settings after the filtering function is turned on cannot be performed.

  On the other hand, according to the present invention, since it is determined that the data necessary for setting the address is always accepted, it communicates with a specific type of device before the expiration date of the address elapses. Thus, even in the communication device that repeatedly executes the process of setting the address in the own device, it is possible to prevent the address from being automatically set by the communication device due to a setting error of the administrator by the communication device.

  That is, the communication apparatus includes a process execution unit that repeatedly executes the process of communicating with a specific type of apparatus and setting the address in the own apparatus before the expiration date of the address set in the apparatus has elapsed. If applied to the above, the above-mentioned effect is further exhibited (claim 2).

By the way, in the communication apparatus of the present invention, the first execution control unit provides the processing execution unit with data determined to be received by the reception determination unit, which is interposed between the network interface and the processing execution unit. The data determined not to be accepted by the means can be discarded without being provided to the process execution means. In addition, in the communication apparatus of the present invention, the process execution unit actively acquires received data from the network interface, and the first execution control unit does not receive the reception determination unit prior to the reception of received data by the process execution unit. The data determined to be discarded can be discarded from the network interface (buffer).

  In the above description, the DHCP server is taken as an example of the specific type of device. However, when a network based on IPv6 (Internet Protocol Version 6) is assumed, the IP address prefix is held as the specific type of device. A router etc. can be mentioned.

Further, when a DHCP server is assumed as a specific type of device, the communication device issues an address to the communication device via the network interface as one step of processing in which the process execution unit sets the above-described address in the own device. the requests to a particular species of the device, the response data to the request, the network interface receives, acceptance judging means, the data, as the data required for setting the address to the own device, determines that the accepted Can be configured.

  When the address is automatically set using a DHCP server, etc., when the data necessary for address setting is received from a specific type of device by operating spontaneously from the communication device, If the response data is handled as data necessary for address setting, it is possible to easily determine whether the received data is data necessary for address setting, and to make a high-speed determination in the reception determination means. Can do.

  In addition, if communication with a specific type of device (request for address issuance and reception of response data) is performed through a dedicated port, the data received at the dedicated port is necessary for address setting. This is convenient because it can be handled as data.

According to a third aspect of the present invention, when the received data is data transmitted with a predetermined port used for data communication with a specific type of device as a destination, the received data is an address on the network. The data determining means determines that the data is necessary for setting the data in the communication device .

According to this communication apparatus, data received at the dedicated port is determined as data necessary for address setting, so that the determination by the data determination means can be performed at high speed.

Further, the above-described reception determination means can be configured as described in claims 5 and 6 . According to a fifth aspect of the present invention, if the data received by the network interface is data transmitted from a device to which a preset address to be rejected is assigned , the acceptance judgment unit of the communication device does not accept the data. If the data received by the network interface is not data transmitted from the device to which the address to be rejected is assigned, it is determined that this data is accepted .

In the communication apparatus in which the reception determination unit is configured as described above, even if the administrator mistakenly sets the address of the DHCP server as the address to be rejected , the automatic setting of the address using the DHCP server is not hindered. . Therefore, according to the present invention, it is possible to prevent an address from being automatically set due to an administrator's mistake.

Furthermore, acceptance judging unit in the communication apparatus according to claim 6, wherein, if the data network interface has received a data transmitted from a device assigned a preset address of the reception subject has, the data If the data received by the network interface is not data transmitted from the device to which the address to be accepted is assigned, it is determined that this data is not accepted .

In a communication apparatus in which the reception determination unit is configured in this way, even if an administrator mistakenly forgets to set the address of the DHCP server as the reception target address, automatic setting of the address using the DHCP server is hindered. There is no. Therefore, according to the present invention, it is possible to prevent an address from being automatically set due to an administrator's mistake.

The first execution control means definitive the above-described communication apparatus, as claimed in claim 7, wherein, after the activation of the communication device, the period until the address in the communication device is first set, by acceptance judging means Regardless of the determination result, the network interface may be configured to accept data received by the network interface and cause the processing execution unit to execute processing based on the data received by the network interface. If the filtering function is not turned on until the address is set in the own device, even if the administrator makes a mistake, the initial address setting can be prevented. In addition, if the filtering function is turned on in this way, the processing load for the first address setting can be suppressed rather than turning on the filtering function before the first address setting.

Moreover, the function as each means in the communication apparatus mentioned above can be realized in a computer by a program.
A program according to claim 8 is a processing execution means for communicating with a computer in a network via a network interface and executing processing based on data received via the network interface to a computer of a communication device having a network interface. Based on the address on the network assigned to the transmission source device of the received data, whether or not the network interface accepts the received data is determined, and the reception determining means determines that the received data is not accepted. The first execution control means for causing the process execution means to execute processing based on the received data when the reception determining means determines that the received data is to be discarded. Do not accept the received data by the judging means Data determination for determining whether or not the received data is data necessary to set an address on the network transmitted from a specific type of device in the network to the communication device. If the received data determined not to be accepted by the means and the acceptance judging means is data necessary for setting the address on the network to the communication device by the data judging means, the first execution This is a program for realizing a function as a second execution control unit for prohibiting the discarding of the received data by the control unit and causing the process execution unit to execute a process of setting an address in the communication device based on the received data. . According to this program, the communication apparatus according to claim 1 can be configured.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is an explanatory diagram illustrating a configuration of a communication system 1 including a printer device 10 to which the present invention is applied. The communication system 1 according to the present embodiment includes a gateway device 3 connected to a wide area network, a DHCP server 5, a printer device 10, and a PC (personal computer) 30. The printer device 10, the PC 30, and the DHCP server 5 are each configured to be capable of TCP / IP communication. The communication system 1 includes a single LAN (local network) including the printer device 10, the PC 30, and the DHCP server 5. Area network) has been established.

  The printer device 10 includes a CPU 11 that executes various programs and controls each unit in the device, a ROM 13 that stores various programs executed by the CPU 11, a RAM 15 that is used as a work area when the CPU 11 executes programs, and various settings. NVRAM 17 serving as a data rewritable nonvolatile memory for storing data, a printing unit 21 for forming (printing) an image on a paper medium, a display unit (liquid crystal monitor), and a user can be controlled by the CPU 11 A display operation unit 23 including an operation unit (key group), a communication control unit 25 that performs communication control by a TCP / IP method, and a network interface (so-called LAN interface) 27 connected to a LAN are provided.

  In FIG. 1, the communication control unit 25 and the CPU 11 are shown separately. However, the communication control unit 25 may be configured by a dedicated device (for example, a dedicated microcomputer), or performs TCP / IP communication with the CPU 11. It may be realized by executing a software group (protocol stack) for realizing. In the present embodiment, it is assumed that the processing in the communication control unit 25 is realized by a program.

  In this embodiment, the printer device 10 communicates with other devices in the LAN, and a task for realizing a predetermined function is executed by the CPU 11. The communication control unit 25 performs these tasks. And relays data exchanged between other devices in the LAN. FIG. 2 is an explanatory diagram showing an operation (reception operation) of the communication control unit 25 of the printer apparatus 10.

  The communication control unit 25 performs predetermined processing on the transmission data generated by the task to convert the transmission data into an IP packet, and outputs this to the network interface 27 as transmission data. On the other hand, the network interface 27 converts the transmission data generated by the communication control unit 25 into an electrical signal for transmission to the LAN, outputs this to the LAN, and converts it into an electrical signal received from the LAN. Based on this, the received signal is converted into digital data that can be received by the communication control unit 25. This is stored in a built-in buffer.

  The communication control unit 25 extracts the received data from the buffer of the network interface 27, determines a task of a delivery destination based on information such as a port number indicated by the received data, and provides the received data to the corresponding task. .

  For example, when the port number indicated in the received data is a port number for network printing, the communication control unit 25 provides the received data to the print job registration processing task. When the print job registration processing task communicates with the PC 30 via the communication control unit 25 and the network interface 27 and receives print command data from the PC 30, the print job for the print data stored in the print command data is queued. To register. The print job registered in the queue is processed by the print control processing task. Specifically, the print control processing task executes the print jobs registered in the queue in the oldest order, and causes the printing unit 21 to print out an image based on the corresponding print data.

  In addition, when the port number indicated in the received data is a port number for setting change, the communication control unit 25 provides the received data to the setting change processing task. When the setting change processing task communicates with the PC 30 via the communication control unit 25 and the network interface 27 and receives setting command data generated by the PC 30 by an input operation on the PC 30 by the user, the setting change processing task receives the setting command data. Based on this, the filtering setting data stored in the NVRAM 17 is updated, and the setting change relating to the filtering function of the printer device 10 is performed.

  The communication control unit 25 according to the present embodiment has a filtering function, operates based on the filtering setting data stored in the NVRAM 17, and a predetermined IP address is set during the period when the filtering function is set to ON. The configuration is such that the received data attached as the source address is discarded and the operation of providing the received data to the corresponding task is not performed. As is well known, in IP communication, information on the IP address of the transmission source is added to the IP packet. Therefore, the communication control unit 25 attaches a predetermined IP address as the transmission source address based on the information on the transmission source address. The received data is discarded.

  FIG. 3 is an explanatory diagram showing the configuration of the filtering setting data stored in the NVRAM 17 of the printer apparatus 10. The filtering setting data is data that determines the operation content of the filtering function, and includes function on / off setting data, mode setting data, and target range setting data.

  The function on / off setting data is data for switching on / off of the filtering function, and is data indicating a value of either “valid” or “invalid”. When the function on / off setting data indicates a value of “valid”, the communication control unit 25 turns on the filtering function. When the function on / off setting data indicates a value of “invalid”, the communication control unit 25 turns off the filtering function.

  Further, the mode setting data is data indicating a value of either “permission mode” or “prohibition mode”. As will be described in detail later, when the mode setting data indicates a value of “permitted mode”, the communication control unit 25 in the present embodiment starts from the device to which the IP address within the range indicated by the target range setting data is assigned. Is allowed to accept the data, and provides this data to the corresponding task, prohibits the acceptance of data from other devices, and discards the data.

  Further, when the mode setting data indicates a value of “prohibited mode”, the communication control unit 25 prohibits reception of data from a device to which an IP address within the range indicated by the target range setting data is assigned. The operation of discarding this data is performed, the reception of data from other devices is permitted, and the operation of providing this data to the corresponding task is performed.

  In addition, the target range setting data is data indicating an IP address range (address range) to be filtered. The address range is described by IP address information and mask information indicating valid address values. For example, when the IP address information is “10.134.0.0” and the mask information is “255.255.0.0”, the upper 16 bits have the value “10.134”. Address is subject to filtering.

  That is, the setting command data transmitted from the PC 30 includes this function on / off setting data, mode setting data, and target range setting data, and the setting change processing task uses the setting command data as a communication control unit. When the data is received via 25, each value of the filtering setting data is updated to a value that matches these data, and the setting is changed according to the setting command data. FIG. 4 is an explanatory diagram showing the operation content of the setting change processing task.

  In addition, when the port number indicated in the received data indicates the DHCP port number, the communication control unit 25 provides the received data to the DHCP client processing task. The DHCP client processing task communicates with the DHCP server 5 and sets the IP address issued (lease) from the DHCP server 5 in the communication control unit 25 of the own device. The printer device 10 according to the present embodiment realizes automatic IP address setting by the operation of the DHCP client processing task, and allows the own device to participate in the TCP / IP network. In other words, the own apparatus is allowed to perform unicast TCP / IP communication with the apparatus in the LAN.

  Next, the operation of the printer apparatus 10 will be described in detail using a flowchart. FIG. 5 is a flowchart showing a boot process executed according to the boot program immediately after the CPU 11 of the printer apparatus 10 is started (immediately after the printer apparatus 10 is turned on).

  When the boot process is executed, the CPU 11 first executes an initialization process to initialize each unit in the apparatus (S110). When this initialization process is completed, the status flag is reset and set to OFF ( S120). The status flag value (on / off) is stored in the RAM 15. As will be described in detail later, this status flag is used to turn on / off the filtering function of the communication control unit 25 (see FIG. 8).

  When the process in S120 is completed, the CPU 11 activates the communication control unit 25 in S125, and activates a DHCP client processing task in S130. After the DHCP client processing task is started, it is determined whether or not an IP address has been set for the device by the operation of the DHCP client processing task (S140). If the IP address has not been set (S140) No in S140), it is determined whether a predetermined standby end condition is satisfied (S150). In S150, the boot program may be configured to determine that the standby end condition is satisfied when a predetermined time has elapsed, or the number of executions of processing related to acquisition of an IP address (for example, a parameter RetryCount described later). If the value) exceeds a predetermined number of times, the boot program may be configured to determine that the standby end condition is satisfied.

  If it is determined that the standby end condition is not satisfied (No in S150), the CPU 11 waits until an IP address is set or the standby end condition is satisfied. If the IP address is set (Yes in S140) or the standby end condition is satisfied (Yes in S150), the process proceeds to S160, and the status flag stored in the RAM 15 is set to ON.

  When the process in S160 is completed, the CPU 11 starts up various application programs determined in advance, and activates the above-described print job registration processing task, setting change processing task, and the like. Thereafter, the boot process ends.

  Next, the DHCP client processing task activated in S130 will be described. FIG. 6 is a flowchart showing DHCP client processing realized by the DHCP client processing task (CPU 11). This DHCP client processing task executes DHCP client processing according to a program stored in the ROM 13.

  When activated, the DHCP client processing task first resets the lease time update flag and sets it off. The value of the lease time update flag is stored in the RAM 15 (S410). When the processing in S410 is completed, the DHCP client processing task sets the permitted port number for the communication control unit 25, opens the above-described DHCP port (S420), and then executes the address acquisition processing. , A DHCP DISCOVER message and a DHCP REQUEST message are sent to the LAN via the communication control unit 25 and the network interface 27. Thus, the DHCP server 5 is requested to issue (lease) the IP address to the printer device 10 (S430). FIG. 7 is a flowchart showing the address acquisition process.

  When the address acquisition process is started, the DHCP client processing task sets the parameter RetryCount to zero, and stores the value of the parameter RetryCount in the RAM 15 (S510). When the process in S510 is completed, the process proceeds to S520, where the lease time setting flag is reset and set to OFF. The value of the lease time setting flag is stored in the RAM 15.

  When the processing in S520 ends, the DHCP client processing task determines whether or not the lease time update flag is set on (S530), and determines that the lease time update flag is not set on (S530). No), a DHCP DISCOVER message for requesting the lease of the IP address is sent in the LAN via the communication control unit 25 and the network interface 27 in the form of bloatcast (S540). This action causes the DHCP client processing task to search for available DHCP servers.

  In this address acquisition process, communication is performed with the DHCP server 5 using a dedicated port (DHCP port). That is, the above-mentioned DHCP DISCOVER message and a DHCP REQUEST message described later are sent to the LAN with the DHCP port number added as the source port number. In addition, when the process in S540 is executed, the IP address of the own device is not set, and therefore, information on the source address of the value “0.0.0.0” is added to this DHCP DISCOVER message (IPv4 in the case of).

  When the DHCP DISCOVER receives this DHCP DISCOVER, the DHCP server 5 is a message including IP address information that can be leased to the client as a response message, and adds its own IP address information as the source address information. The DHCP OFFER message is sent to the LAN in the form of a broadcast (however, when sending a response message, the message is sent with the source port number as the destination according to the source information of the message that caused the response message to be sent). (The same applies to DHCP ACK described later.)

After transmitting the DHCP DISCOVER message, the DHCP client processing task determines whether or not the DHCP OFFER message has been received via the network interface 27 and the communication control unit 25 (S550), and during the predetermined time, the DHCP OFFER message Is received, it is determined that the DHCP OFFER message has been received (Yes in S550), and the process proceeds to S560. On the other hand, if the DHCP OFFER message cannot be received even after the predetermined time has elapsed, it is determined that the DHCP OFFER message has not been received at that time (No in S550), and the process proceeds to S573.

  When it is determined Yes in S550 and the process proceeds to S560, the DHCP client processing task selects one of the available DHCP servers 5 found by the reception of the DHCP OFFER message, and the IP address of the selected DHCP server 5 is selected. A DHCP REQUEST message, which is a message including information and is a lease request for an official IP address to the selected DHCP server 5, is transmitted to the LAN via the communication control unit 25 and the network interface 27.

  When the DHCP server 5 receives a DHCP REQUEST message requesting itself to lease an IP address, the DHCP server 5 sends, as a response message, the IP address to be leased and the lease time to the client that has transmitted the DHCP REQUEST message. It is a message including information, and a DHCP ACK message including information on its own IP address is transmitted to the LAN as information on the source address.

  Accordingly, the DHCP client processing task determines whether or not the DHCP ACK message has been received via the network interface 27 and the communication control unit 25 after the transmission of the DHCP REQUEST message (S570). If a DHCP ACK message for the requested IP address is received within a predetermined time, it is determined that the DHCP ACK message has been received (Yes in S570), and the process proceeds to S580. If the DHCP ACK message cannot be received even after the predetermined time has elapsed, it is determined that the DHCP ACK message has not been received at that time (No in S570), and the process proceeds to S573. .

  When the process proceeds to S573, the DHCP client processing task adds 1 to the value of the parameter RetryCount, and then determines whether or not the value of the parameter RetryCount exceeds the specified value (S577). If it is determined that the value of the parameter RetryCount exceeds the specified value (Yes in S577), the address acquisition process is terminated. If it is determined that the value does not exceed the specified value (No in S577), the process proceeds to S540. Then, try to access the DHCP server again.

  On the other hand, when the process proceeds to S580, the DHCP client processing task automatically instructs the communication control unit 25 based on the IP address information leased to the device and the lease time information included in the received DHCP ACK message. Set the IP address of the device. When the processing in S580 is completed, the DHCP client processing task sets the lease time setting flag to ON (S590). Thereafter, the address acquisition process ends.

  In addition, when the DHCP client processing task determines that the lease time update flag is set to ON (Yes in S530), the DHCP client processing task proceeds to S600 and the lease time for the IP address set for the communication control unit 25. If it is determined whether or not the lease time has elapsed (Yes in S600), the lease time update flag is reset and set to off (S610). Thereafter, the process proceeds to S540.

  On the other hand, if it is determined that the lease time has not elapsed (No in S600), the DHCP client processing task sets the value of the parameter RetryCount to zero (S620). Thereafter, the DHCP client processing task sends a DHCP REQUEST message into the LAN via the communication control unit 25 and the network interface 27 to the same DHCP server 5 as the DHCP server 5 selected in the previous S560 (S630). ).

  When this processing is completed, the DHCP client processing task determines whether or not the DHCP ACK message has been received via the network interface 27 and the communication control unit 25 (S640), and requests the requested IP for a predetermined time. When the DHCP ACK message for the address is received, it is determined that the DHCP ACK message has been received (Yes in S640), and the process proceeds to S650. If the DHCP ACK message cannot be received even after the predetermined time has elapsed, it is determined that the DHCP ACK message has not been received at that time (No in S640), and the process proceeds to S643. .

  In S643, the DHCP client processing task adds 1 to the value of the parameter RetryCount, and then determines whether or not the value of the parameter RetryCount exceeds the specified value (S647). If it is determined that the value of the parameter RetryCount exceeds the specified value (Yes in S647), the address acquisition process is terminated. If it is determined that the value does not exceed the specified value (No in S647), the process proceeds to S630. . It then tries again to access the DHCP server.

  On the other hand, when the process proceeds to S650, the DHCP client processing task automatically instructs the communication control unit 25 based on the IP address information leased to the device and the lease time information included in the received DHCP ACK message. Set the IP address of the device. When the process in S650 is completed, the lease time setting flag is set to ON (S660). Thereafter, the address acquisition process ends.

  In S430, when the address acquisition process described above is completed, the DHCP client processing task cancels the permitted port number for the communication control unit 25 and closes the DHCP port described above (S440). When the processing in S440 is finished, the DHCP client processing task determines whether or not the lease time setting flag is on (S450), and determines that the lease time setting flag is on (Yes in S450). , The process proceeds to S460.

In S460, the DHCP client processing task sets the value of the parameter SleepTime to the lease time set in S580 or S650 × 0.5.
SleepTime = lease time x 0.5
After this setting, the DHCP client processing task sets the lease time update flag to ON (S470) and starts a time counter (not shown) (S490). Based on the count value of the time counter, after the time counter is activated, the system waits until a time corresponding to the value indicated by the parameter SleepTime elapses (S495). When the time corresponding to the value indicated by the parameter SleepTime has elapsed (Yes in S495), the DHCP client processing task proceeds to S420 and executes the above-described processing after S420.

  In S460, SleepTime is set to a half of the lease time because the IP address from the DHCP server 5 is reserved with a margin before the expiration date (lease time) of the IP address set in the own device elapses. This is for reacquisition. When the lease time of the IP address expires, the printer device 10 cannot participate in the TCP / IP network. Therefore, in the DHCP client processing task, before the expiration date of the set IP address elapses, The process of communicating and setting the IP address in the own apparatus (the process of S420 to S495) is repeatedly executed.

  In addition, when the DHCP client processing task determines that the lease time setting flag is off (No in S450), the parameter SleepTime is set to the specified time T1 (for example, T1 = 3 minutes). Thereafter, the process proceeds to S490, and the above-described processing is executed.

  Further, when activated, the communication control unit 25 activated prior to the DHCP client processing task executes a reception control process shown in FIG. FIG. 8 is a flowchart showing a reception control process repeatedly executed by the communication control unit 25. The filtering function described above is realized by this reception control process.

  When the reception control process is executed, the communication control unit 25 waits until the network interface 27 receives data (IP packet) from a device in the LAN (S810), and when the network interface 27 receives data (Yes in S810). ) Based on the filtering setting data stored in the NVRAM 17, it is determined whether or not the filtering function is turned on (S820). Specifically, when the function on / off setting data constituting the filtering setting data indicates a value of “valid”, it is determined that the filtering function is turned on, and the function on / off setting data is “invalid”. When the value of is shown, it is determined that the filtering function is not turned on (turned off).

  If it is determined that the filtering function is not turned on (No in S820), the communication control unit 25 proceeds to S870 and accepts data received by the network interface 27. That is, the received data is provided to the task corresponding to the port number indicated by the received data. Thereafter, the reception control process ends.

  However, in S870, the data received by the network interface 27 is provided to the corresponding task only when the port number indicated by the received data is set to the permitted port number (that is, the corresponding port is Only when open). When the port number indicated by the received data is not set as the permitted port number, the communication control unit 25 performs an operation of discarding the received data even after the process proceeds to S870.

  On the other hand, if it is determined that the filtering function is turned on (Yes in S820), the communication control unit 25 proceeds to S830 and determines whether the status flag is set to on. If it is determined that the status flag is not set to ON (No in S830), the process proceeds to S870, and the data received by the network interface 27 is provided to the corresponding task. Thereafter, the reception control process ends.

  On the other hand, if it is determined that the status flag is set to ON (Yes in S830), the communication control unit 25 proceeds to S840 and determines whether or not the mode setting data indicates a value of “permitted mode”. To do. If the mode setting data indicates a value of “permitted mode”, the process proceeds to S850.

  After shifting to S850, the communication control unit 25 collates the address range indicated by the target range setting data stored in the NVRAM 17 with the transmission source address indicated by the reception data, and the transmission source address indicated by the reception data is the target range setting data. It is determined whether it is included in the address range indicated by (S860). Based on this determination, the communication control unit 25 determines whether or not the transmission source device is a reception target device registered in the target range setting data based on the address range information.

  If it is determined that the transmission source address indicated by the received data is included in the address range indicated by the target range setting data (Yes in S860), the communication control unit 25 proceeds to S870 and the network interface 27 receives the data. Provide the data to the corresponding task. Thereafter, the reception control process ends.

  On the other hand, when determining that the transmission source address indicated by the received data is not included in the address range indicated by the target range setting data (No in S860), the communication control unit 25 proceeds to S900 and the port indicated by the received data It is determined whether the number is a DHCP port number. When it is determined that the port number indicated by the received data is a DHCP port number (Yes in S900), the process proceeds to S870, and the data received by the network interface 27 is transferred to the corresponding task (DHCP client processing task). provide.

  That is, in this embodiment, when the network interface 27 receives data destined for the DHCP (dedicated) port, it should be accepted according to the content of the target range setting data by determining Yes in S900. Even if there is no data, it is determined that the data is accepted, the process proceeds to S870, and the data received by the network interface 27 is provided to the corresponding task (DHCP client processing task). Thereafter, the reception control process ends.

  On the other hand, if it is determined in S900 that the port number indicated by the received data is not a DHCP port number, the communication control unit 25 proceeds to S910 and does not accept the data received by the network interface 27 ( That is, the received data is discarded (data is erased) without providing data to the corresponding task).

  That is, in this embodiment, when the data received by the network interface 27 is not data destined for the DHCP (dedicated) port, it is determined that the data is not accepted according to the contents of the target range setting data (S900). No), the received data is discarded (S910). Thereafter, the reception control process ends.

  In addition, if the communication control unit 25 determines in S840 that the mode setting data does not indicate a value of “permitted mode” (in other words, the mode setting data indicates a value of “prohibited mode”). If YES, the process proceeds to S880.

  After shifting to S880, the communication control unit 25 collates the address range indicated by the target range setting data stored in the NVRAM 17 with the transmission source address indicated by the reception data, and the transmission source address indicated by the reception data is the target range setting data. Is determined to be included in the address range indicated by (S890).

  If it is determined that the transmission source address indicated by the received data is not included in the address range indicated by the target range setting data (No in S890), the communication control unit 25 proceeds to S870 and the network interface 27 receives the data. Provide the data to the corresponding task. Thereafter, the reception control process ends.

  On the other hand, when determining that the transmission source address indicated by the received data is included in the address range indicated by the target range setting data (Yes in S890), the communication control unit 25 proceeds to S900, and the port indicated by the received data It is determined whether the number is a DHCP port number. When it is determined that the port number indicated by the received data is a DHCP port number (Yes in S900), the process proceeds to S870, and the data received by the network interface 27 is transferred to the corresponding task (DHCP client processing task). provide. Thereafter, the reception control process ends.

  On the other hand, if it is determined in S900 that the port number indicated by the received data is not a DHCP port number, the communication control unit 25 proceeds to S910 and does not accept the data received by the network interface 27 ( That is, the received data is discarded (data is erased) without providing data to the corresponding task). Thereafter, the reception control process ends. In this way, the filtering function is realized by the reception control process.

  The communication system 1 according to the present embodiment has been described above. In the present embodiment, until the IP address is set in the printer device 10 after the printer device 10 is started by turning on / off the status flag. The filtering function of the communication control unit 25 is prevented from working. Therefore, according to the present embodiment, if the DHCP server 5 obeys the target range setting data by making an incorrect setting to the printer device 10 through the PC 30 or the like, the rejection target device (outside the reception target device) Even in such a case, communication between the printer device 10 and the DHCP server 5 can be prevented from being interrupted.

  Therefore, according to the present embodiment, it is possible to prevent the printer device 10 from being unable to perform automatic address setting due to a setting error for the printer device 10 by the administrator. Therefore, according to the present embodiment, it is possible to prevent the printer device 10 from being unable to participate in the TCP / IP network due to an administrator setting the printer device 10 for an incorrect filtering function. .

  Further, in this embodiment, with respect to received data destined for the DHCP port, if the DHCP server 5 obeys the target range setting data by preventing the filtering function from reaching, the rejection target device (acceptance target device) The communication between the printer apparatus 10 and the DHCP server 5 is not disturbed even in the case where the error occurs.

  Therefore, in this embodiment, the DHCP client processing task repeatedly communicates with the DHCP server 5 in accordance with the expiration date of the leased IP address, acquires information on the leased IP address from the DHCP server 5, and obtains the address. Even in the case of automatic setting, this operation is not disturbed by the filtering function. Therefore, according to the present embodiment, in a system in which an IP address needs to be automatically set continuously, the printer device 10 can make a TCP / IP network when the administrator makes an incorrect setting to the printer device 10. Can be prevented from becoming unable to participate.

The communication device of the present invention corresponds to the printer device 10, and the processing execution means corresponds to a print job registration processing task, a setting change processing task, and a DHCP client processing task.
In addition, in the reception control process, the reception determination unit determines whether or not to accept data transmitted from the device in accordance with a determination criterion such as whether the IP address of the transmission source device is in the address range indicated by the target range setting data. This is realized by the operation of determining (S860, S890) . Further, in this embodiment, the address of the refused Target is defined by the target range setting data in the "prohibition mode", the address of the reception subject is defined by the target range setting data in the "permission mode" Yes.

Further, the first execution control means (execution control means) of the present invention discards the received data in S910 when it is determined that it is not accepted (when No is determined in S860 or Yes in S890 ). On the other hand, if it is determined that the data is accepted (Yes in S860 or No in S890 ), the received data is provided to the corresponding task in S870, and the data determined to be accepted. This is realized by the operation of the communication control unit 25 that selectively causes the corresponding task to execute the process.
In addition, if the data judging means judges that the data is not accepted (when judged as No in S860 or when judged as Yes in S890), the destination port number indicated in the received data is the one for DHCP. This is realized by the operation of determining whether or not it is a port number (S900).
In addition, when the destination port number indicated in the received data is the DHCP port number, the second execution control unit determines Yes in S900, and regardless of the content of the target range setting data, the received data Is provided to the corresponding task in S870, and the processing for the data is realized by an operation for causing the corresponding task to execute.

In addition, according to the present invention , “a period from when the communication device is activated until an address is first set in the communication device, the processing based on the data received by the network interface is performed regardless of the determination result by the reception determination unit. The operation to be executed by the execution means is to turn off the status flag for the period until the address is set in the communication device after the communication device is started, and turn on the status flag after the IP address is set in the own device. (S160) .

  Further, the communication device of the present invention is not limited to the above embodiment, and can take various forms. For example, in the above embodiment, the address range is described by the IP address information and the mask information. However, the address range may be defined by a description from what number to what number. In addition, the TCP / IP communication in the LAN may be realized by IPv4 (Internet Protocol Version 4) or may be realized by IPv6.

It is explanatory drawing showing the structure of the communication system 1 provided with the printer apparatus 10 with which this invention was applied. It is explanatory drawing which shows the reception operation | movement of the communication control part 25. FIG. It is explanatory drawing showing the structure of filtering setting data. It is explanatory drawing which showed the operation content of the setting change process task. It is a flowchart showing the boot process which CPU11 performs immediately after starting. It is a flowchart showing the process implement | achieved by a DHCP client process task. It is a flowchart showing the address acquisition process implement | achieved by the DHCP client process task. 4 is a flowchart illustrating a reception control process executed by a communication control unit 25.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Communication system, 3 ... Gateway apparatus, 5 ... DHCP server, 10 ... Printer apparatus, 11 ... CPU, 13 ... ROM, 15 ... RAM, 17 ... NVRAM, 21 ... Printing part, 23 ... Display operation part, 25 ... Communication Control unit, 27 ... network interface, 30 ... PC

Claims (8)

A communication device comprising a network interface,
Processing execution means for communicating with a device in the network via the network interface and executing processing based on data received via the network interface;
Whether or not to accept the data that the network interface receives a reception determining means for determining based on an address on the network assigned to the source device of the received data,
When it is determined that the reception data is not received by the reception determination unit, the reception data is discarded, and when it is determined that the reception data is received by the reception determination unit, a process based on the reception data is performed. First execution control means to be executed by the process execution means;
If the reception determining means determines that the received data is not received, the received data is necessary for setting the address on the network transmitted from a specific type of device in the network to the communication device. Data judging means for judging whether or not the data is correct,
When the received data determined not to be received by the reception determining unit is data necessary for setting the address on the network in the communication device by the data determining unit, the first data A second execution control means for prohibiting the discarding of the received data by the execution control means, and causing the process execution means to execute a process of setting an address in the communication device based on the received data;
Communication device comprising: a. The process execution means is configured to repeatedly execute the process of communicating with the specific type of device and setting the address in the communication device before the expiration date of the address set in the communication device elapses. The communication apparatus according to claim 1, wherein: The data determination means, when the received data is data transmitted with a predetermined port used for data communication with the specific type of device as a destination, the received data indicates an address on the network. 3. The communication apparatus according to claim 1, wherein the communication apparatus is configured to determine that the data is necessary for setting in the communication apparatus. The communication device according to claim 1, wherein the specific type of device is a DHCP (Dynamic Host Configuration Protocol) server. The reception determination means determines that the data received by the network interface is not received when the data transmitted from a device to which a preset address to be rejected is assigned , claim data that the network interface has received, wherein when the address of the rejected target assigned device not data sent from is characterized by being a configuration to determine that accepts this data 1 The communication apparatus according to claim 4 . If the data received by the network interface is data transmitted from a device to which a preset reception target address is assigned , the reception determination unit determines that the data is received, and the network The data received by the interface is configured to determine that the data is not accepted when the data is not transmitted from a device to which the address to be accepted is assigned. The communication apparatus according to claim 4 . The first execution control means receives the network interface during the period until the address is first set in the communication apparatus after the communication apparatus is activated, regardless of the determination result by the reception determination means. The communication apparatus according to claim 1, wherein the communication apparatus is configured to receive data and cause the process execution unit to execute a process based on the data received by the network interface. In a computer of a communication device having a network interface,
  Processing execution means for communicating with a device in the network via the network interface and executing processing based on data received via the network interface;
  An acceptance determination means for determining whether or not to accept the data received by the network interface based on an address on the network assigned to the transmission source device of the received data;
  When it is determined that the reception data is not received by the reception determination unit, the reception data is discarded, and when it is determined that the reception data is received by the reception determination unit, a process based on the reception data is performed. First execution control means to be executed by the process execution means;
  If the reception determining means determines that the received data is not received, the received data is necessary for setting the address on the network transmitted from a specific type of device in the network to the communication device. Data judging means for judging whether or not the data is correct,
  When the received data determined not to be received by the reception determining unit is data necessary for setting the address on the network in the communication device by the data determining unit, the first data Second execution control means for prohibiting discarding of the received data by the execution control means and causing the process execution means to execute a process of setting an address in the communication device based on the received data
  A program to realize the functions as

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